U.S. Pat. No. 6,245,010B1 (to be referred to as “the above prior patent reference” hereinafter) discloses an open type incubator (a so-called infant warmer) including an infant mat, which is substantially rectangular when seen from the top, to lay an infant such as an immature infant thereon, and a heater capable of radiating heat rays toward the upper surface of the mat. As the open type incubator of the above prior patent reference, the first example that uses a substantially rod-like heat generator and the second example that uses a substantially spherical heat generator are shown.
In the open type incubator as the first example of the above prior patent reference, the heater is arranged substantially right above the infant mat. As the length of the heater in the back-and-forth direction is substantially equal to that of the infant mat in the back-and-forth direction, the rod-like heat generator can warm the entire upper surface of the infant mat substantially uniformly. The open type incubator as the second example of the above prior patent reference includes a substantially spherical heat generator and a substantially hemispherical reflecting plate which covers substantially the upper surface of the heat generator from above. When seen from the top, the heater is arranged at a position sufficiently displaced from the center toward the head-side end of the upper surface of the infant mat. Thus, when, e.g., X-ray imaging an infant on the mat, the heater need not be retracted to another location.
In the open type incubator as the first example of the above prior patent reference, however, when, e.g., X-ray imaging an infant on the mat, the heater need be retract to another location. This retraction is cumbersome to perform, and renders the structure of the open type incubator complicated. Due to an erroneous operation or the like, the heater may accidentally come into contact with the X-ray imaging apparatus or the like, damaging both of them. Furthermore, since the head of a personnel attending to the infant on the mat may block the heat rays from the heater, the heater may not be able to exhibit its original performance sufficiently. Also, the head (particularly the back head part) of the attending personnel may be accidentally heated.
In the open type incubator as the second example of the above prior patent reference, since the upper surface of the mat is warmed using the substantially spherical heat generator and the substantially hemispherical reflecting plate, that round portion of the upper surface of the mat which is in a region including the center and its vicinity is warmed mainly. As the mat is substantially rectangular when seen from the top, the regions including the four corners of the upper surface of the mat and their vicinities are not warmed like the region including the center and its vicinity. Hence, when the infant is to undergo resuscitation or various types of other medical treatments or procedures, the infant must first be laid in the region including the center of the upper surface of the mat and its vicinity. This may impose restrictions on the treatments or procedures.